Electric heating device.



PATENTED JUNE 16, 1908.

W. HADAWAY, JR. ELECTRIC HEATING DEVICE.

APPLICATION T7331) JULY 3, 1907. V

j a 1 I I (If lllllllllllllllllll *WEPLIAIVI v tY JR, 1

concern: I, at l, YI'LLIAM HADAWAY, l United States, and sige, in thecounty of Essex Jersey, have invented a I mprovement in Electric 3'which the following is a ,teinperatur'e' Resistance units that are adated for heating such devices are obvious y subjectedito heat conditionswhich are damaging toordin'ary forms of insulation.

According -to ,my present invention, I provide a novel resistance unitwhich is specially compact informand which employs an insulation that isadmirably adapted to the service conditions: to which the resistanceunit is subjected; Furthermre,-I combine the resistance :with :a sadironin an improved manner,,J-, whereby;the best results are obtained with aminimum expenditure of en-v gy I, l A. E, Figure 1,,0f1 the accompanyingdrawings, is erspective view of an electrically heated ,saiilironconstructed and arranged in accordance with mylinyntion. Fig. 2 is aplan '1 i'ew of the resistance unit and one of the insulating platesemployed in the device shown in Fig.-1.- Fig.1?) is a plan or face viewof one x of theinsulatmgplates and Fig. 4 is a detail ,v'i'ew oftheuni'tj shown in Fig. 2.

Referringto the drawings, the device here illustrated comprises .arelatively thick plate 1 of iron or other suitable material having asmooth ironing surface 2, a body member 3 havinga handle 4, and aresistance unit 5. The resistance unit com rises a notched insulatingplate 6 around w ich a resistance ribbon 7 is wound in the form of aflattened helix, and insulating plates Sand 9 upon the respective sides'of the flattened helix,

NEW Jun, 'COLQAFQOl-HORAHU 'QFNEW roles: 1

-- n rlncrnre DEVIUEA 1 Specification m? Letters Patent;

hpplication. filed July 3, 19m. Serial No. 382,395.

tialthat a-relatively. large mass of heat-coir ilymaintainedat 'asubstantially constant --A'SSTGNORTO Han ers r i l ateritect Jun- 16, i9081 The plate 9 is provided with slots 10 through which the extremitiesof the esistance ribbon project, to be attached to t'e rminals 11 and12.

The assembled resistance unit is interposed between the plate 1 and thebodyB of the sadiron and the insulating plates are preferably built upof relatively small overlapping pieces of sheet mica held together by asuitable insulating shellac, in order that the plates may soften underthe-lieatand pressure, which are applied inassembling the iron andthereby act as a gasket or cushion to equalize the pressure.

The body 3 is recessed to receive the resistance unit leads and a coverplate 13,130 which. the handle a is affixed, is removably attached to itafter the other parts are .assembled.

A terminal block 14 is secured to the heel of the iron and serves tosupport the terminals 11 and 12 and to insulate them. from each other. IY

The resistance ribbon is provided with a plurality of lateral slots 15which are alter nately opened at opposite sides of the ribbon to producea zig-zagpath for the current,- whereby a considerable length ofconductor is obtained in a relatively short length of ribbon. The slotsare omitted from the ends of the ribbon and from the portions which arebent in the formation of the "flattened helix, the maximum conductivitybeing-thus, provided at the bends and at the terminals, which wouldotherwisebe most likely to fuse, in the operation of the unit as aheating coil.- Although the slots in the resistance'ribbon are shown asof uniform Width and as unis formly spaced, it may be desirable, in somecases, tovary the widths or spacings in order to concentrate the heat atpredetermined points, 1 n It is conceivable that modifications of sizeand arrangement of details may be effected without departing. from thespirit ofmy inventionand I desire that only such limita-' tions beimposed as are indicated in the appended claims.

Iclaim as my invention: r y 1. A resistance element comprisin' aconducting ribbon having a plum ity 0 groups of slots alternately openat 0p osite edges,

said groups being separated' y'rnaterial lengths of ribbon having arelatively large current-conducting}?apacity.

ing ribbon wound into a flattened helix and provided with a plurality ofgroupsof slots successively open at opposite edges of the ribbon, saidgroups being separated by material lengths oi? ribbon having arelatively large. current-conducting capacity and forming the bendsofthe flattened helix,

4. A resistance unit comprising an insulating plate and a conductingribbon wound thereon in the tormof a flattened helix and slotted toprovide a zigzag path for the current, said slots being only disposedbetween the bends oi' the flattened hchx.

5; A resistance unit comprising a notched insulating plate, a conductingribbon wound around the plate into a flattened helix, said ribbon havinglow-resistance sections at the bends of the helix, and a pair of thininsu lating' lates fitted to the respective sides of the he L p 6. Aresistance-unit'comprising a notched insulating plate, aconductingribbon Wound aroundthe plate into aflattened helix, and a pair of thin insulating plates fitted to the respective sides'of thenotched plate, said ribbon being slotted between the bends of the helixto produce a zigzag path for the current, while a relatively owresistance is main-- tained' in the ribbon at the bends of the helix.

7. A resistance unit comprising a notched insulating plate,

pair of thin insulating plates fitted to its respective sides, with aplurality of groups of slots that are successively open at oppositeribbon, said groups being separated by a material length oflow-resistance ribbon disposed at the bonds of the flattened helix.

8. In an electric sad-iron, the combination with relatively thick metalplates, and a re sistance unit interposed between the plates, said unitcomprising a flattened helix of resistance material, and plates ofinsulating material capable of softening under heat and pressure to forma gasket or cushion between the metal plates.

' 9, In an electric sad-iron,--the combination with relatively thickmetal plate having an.

ironing surface, a body a conducting ribbon Woundaround the plate into aflattened helix, and a said ribbon being provided edges of the membersecured to said plate, and a resistance unit between the body member andthe plate, said unit comprising a conducting ribbon wound into aliartoned helix and having a series of slots v-;hich are openalternately at opposite edges to in.- crease the length of thecurrent-condusting path, and a pair of plates of insulating niatcrialhaving the property of softening under heat and pressure to form agasket between the metal plate and the body ineniber.

10. In an electric sad-iron, the combination with a relativelythickmetal plate having an ironingsurface, a body secured to said plate and aresistance unit interposed between the body member and the plate, saidunit coinprising a conducting ribbon around into a flattened helix andprovided. with a plurality of groups of slots successively open at opposite edges of the ribbon to increase the length of thecurrent-co11ducting path, said groups being separated by ribbon sectionsof rela tively low resistance disposed at the bends in the helix. l

11.. In an electric sad-iron, the combinattion with a relatively thickmetal plate hav ing an ironing surface, a body nrcrobm' sccured to saidplate and a resistanceunit terposed-between the body member and theplate and comprisingplates oi 'nsuh'iting ma terialhaving the propertyof softening under heat and pressure to form a gasket between the metalparts, an intermediate insulating platoond conducting ribbon woundthereon in the form of a flattened helix, said ribbon being slottedbetween the bends in. the helix to produce a zigzag path for thecurrent.

12. In an electric sad-iron, the combination with a relatively thickmetal plate having an ironing surface, a body member secured tosaidplate, and a resistance unit interposed between the body-member andthe plate and comprising anotched insulating plate, a conductingribbonwound around said insulating plate into a flattened helix, and apair of thin insulating plates fitted to the respective sides of thenotched plate, said ribbon being providedwith groups of slots to producea zigzag path [for the current, andsaid groups, being separated bysections of ribbon having relatively low-resistance and. disposed at thebends in the helix. I

, In testimony whereof, I have hereunto subscribed my name this 29th davof June, 1907.

4 WILLIAM S. HADAWAY, J n. Witnesses:

WM. H. CAP'EL,

F. Lownrvnaurr.

